Below is a letter I have written to parents who are hesitant about giving vaccinations to their children. I don’t know who it will convince, but I needed a respectful and informative way to follow up with parents who expressed concerns or declined vaccinations, and this is what I now share with them after such visits. This is written not with the goal of exhaustively proving the case for vaccine safety and efficacy, which would require a longer treatise, but simply to address a few major points trying to address the sources of such parents’ fears and doubts about vaccines.

Dear concerned parent,

I understand that you have concerns, doubts and maybe fears about immunizations, and that as a result you may have chosen not to immunize your child. This is an emotional topic, and I know it is sometimes hard to even articulate exactly what those fears are—you may just feel uncomfortable about them. I appreciate the opportunity to share my perspective with you, and I commit to discuss this with respect for your rights and responsibilities as a parent. But I would like to share my perspective with you in hopes that it will help you to think about immunizations.

Here in the 21st century, many of us have an inherent suspicion of anything synthetic or artificial and are trying to get back to what is naturally healthy. We know that processed foods are bad for us and whole foods are much better. Even though I am a physician, I share those biases. Further, while we may rely on the health care system for certain needs, we tend to have less than full trust that the health care system is really always oriented for our best interest. We also tend not to trust the government, and since immunizations are controlled and pushed by both government and giant companies, they are a natural object of suspicion for us. Plus, there is much written on the Internet, and it is hard to know who really has the correct interpretation of the facts and often even what the facts really are.
Regardless of the reasons, once fear or mistrust has developed, it is very hard to overcome. You may read a lot of positive information about vaccines and still feel uncomfortable. As you think about vaccines more, you may develop more specific questions that you need answered. But I want to tell some history behind the development of two particular vaccines.

The first known immunization was with smallpox in China in the 15th century. Smallpox was a disfiguring and frequently deadly disease present throughout human history. The Chinese developed methods where dried scabs from a smallpox patient would be applied to a patient who had not had smallpox; the inoculated patient would develop a much milder form of smallpox and would become immune to the disease. This type of immunization was later introduced into England and North America in the 1720’s. Later in the 1760’s it was observed that dairy workers would never get smallpox, and it was postulated that they had immunity to smallpox because they had already had cowpox, a related disease that is much milder in humans than smallpox. In the 1790’s Edward Jenner developed a method to vaccinate humans with the cowpox virus to induce immunity against smallpox. During the 1800’s the virus used for immunization against smallpox was changed to vaccinia, another similar virus. Smallpox was eliminated from the United States by 1897 and worldwide eradication was finally accomplished by 1979. For most of us, smallpox is now simply a vague and distant historical fact, rather than the terrorizing disease it once was.

The reason I recounted this story is to remind us that immunization is not quite as new as we tend to think, and that horrible diseases can sometimes be completely eliminated through immunization. Every one of the vaccines we use today has an interesting story that could be helpful to understand, but there is one other story I’d like to tell in this letter, that of the MMR vaccine.

The MMR vaccine is a three-in-one immunization that provides protection for measles, mumps and rubella, but I will focus on measles. Measles in its current form has been present since about 1100 AD. Measles is one of the most contagious viruses known to man; nine out of ten nonimmune people in a room with a measles patient could be expected to get infected. Measles causes a high fever, a rash, and many possible complications including diarrhea, pneumonia, or brain infections. In the United States, measles may kill about 3 in 1000 people infected, but in developing countries it may kill 20-30% of those infected. The measles virus was first isolated in cell culture in 1954 and the first measles vaccine was licensed in 1963. There were several early versions of the vaccine including an inactivated (killed) virus and a live attenuated (i.e., weakened) vaccine. There were also several more weakened viruses studied, but by 1968 an even weaker live attenuated version was licensed, and this version has been used in the United States ever since. In 1978 the CDC announced a campaign with the goal of completely eliminating measles from the country, and by 1981 the number of cases annually had dropped 80%. New outbreaks of measles in 1989 prompted a recommendation for a second or “booster” dose of MMR to increase immunity to nearly 100%. Measles was virtually eliminated from the USA by 2000, but unfortunately, that is not the end of this story.

In the case of vaccines, although there may have always been some level of fear about them, those fears were multiplied when, in 1998, Dr. Andrew Wakefield published in the Lancet, a prestigious British journal, a study proposing a link between the MMR vaccine and autism. The study had a huge effect on public opinion and has given a great deal of fuel to the fire of the ongoing fears and doubts of many about immunizations. However, it turned out that Dr. Wakefield’s research was fraudulent, which ultimately resulted in the loss of his medical license and the retraction of his publication by the journal. Since then, multiple studies of millions of vaccinated vs. unvaccinated children have repeatedly failed to find any association between MMR and autism, but the fear lives on in spite of that. It turns out that doubt is even harder to eliminate than measles itself.

The Disneyland measles outbreak of 2015 has shown us that, when the number of children who are vaccinated drops below some threshold, some vaccine-preventable illnesses can resurge in the population. So in reality, every time a family chooses not to vaccinate a child, the risk of vaccine-preventable diseases actually rises for the entire community.

Can side-effects occur with immunizations? Absolutely, but serious side-effects are exceedingly rare. Some people have written their experiences on the Internet to discourage others from immunizing their children, but while those stories may foment our fears and doubts, those individual horror stories often contain many false assumptions and draw many inaccurate conclusions. It is very easy to stir up fear with even incomplete or inaccurate information, and very hard to eliminate fear once it exists.

Here are the facts as I see them about modern immunizations:

Immunizations have resulted in the elimination or dramatic reduction of many childhood diseases.

The illnesses that are preventable by vaccines range in severity from “major inconvenience and expense” to disfiguring and deadly, but are mostly forgotten because most of us have never seen cases of those diseases.

To maintain the benefits of immunizations, they have to continue in use by a certain percentage of the population as long as the virus continues to exist anywhere in the world. Once usage drops below some level, a vaccine-preventable disease can make a resurgence in the population.

Although doubt is very difficult to dispel, there is overwhelming evidence of the extremely high safety of vaccines, making their risks very low versus benefits that are very great.

I hope this is helpful to you as you consider whether to immunize your child. I believe that immunizations were perhaps the single greatest advance in health care in the 20th century, but we have to continue to use them to continue to reap their benefits.

8 Responses to A Letter to Parents Concerned about Vaccines

Excellent, respectful and sensitive approach! So good to see someone understand the fears of many of us parents.
For the most part, I am thankful I had my children immunized. No chicken pox, etc. to deal with, and we had plenty of medical issues to deal with as it was, without taking on avoidable, unnecessary ones!
In the spirit of support of possibly helping you hone your arguments, I offer you this:
1. When my six month old baby had the MMR vaccine in 1998, I never heard about any claim linking autism to this vaccine until many years later. I didn’t even really know what autism was then. But what I saw happen to my bright, healthy, happy baby boy within a few hours of that vaccine was absolutely frightening. He became socially unresponsive. He would not look at faces. It was as if he was in his own world, and no one else existed. This lasted 3 days. On the second day, I called pediatrician and they said to bring him back in. Doc spent a lot of time with the baby and seemed concerned, very perplexed, but would not say more than “just keep watching him”. So thankful it did turn out to be short lived for us! But for many parents who witnessed something similar with their baby, it was not. I understood the parent movement to be largely based on what many, like me, had actually witnessed happen to their own child (or someone else’s), not on rumors generated by research? I admit I may be wrong, I don’t know. That was just my understanding at the time.
Many years later, I learned “thermosol” or some such preservative that was high in Mercury was used in those MMR vaccines then, meaning that heavy metal Mercury toxicity was responsible for the autistic symptoms, (some of is don’t detox as efficiently as others); but that since all the controversy, it is no longer produced with that ingredient, making it safer now. Is any of all this true, or all just hearsay?
2. I am concerned about the way newborns are first vaccinated in the delivery room. I don’t even remember what it is for, but is it really necessary to give such an onslaught of drugs to a brand new immune system? Why can’t those vaccines just wait until newborn is a little older and more established?
3. I hear rumors of vaccine cocktails containing many more drugs than just 3 as in MMR, being given to children these days. Is this true? And if so, again why so necessary or desirable to overwhelm a child’s immune system this way? Is this really safe? Seems like an awful lot for you g body to handle all at once. Why couldn’t they be spaced out?

Hi Kelli, you ask a lot of good questions and these are just about exactly the issues that many write about. I’ll try to answer as much as a I can.

1. Let me be clear that the 3 days of symptoms your six month old had after MMR vaccination, although perhaps superficially similar, was unlikely to have any relationship to actual autism or autistic spectrum disorder. I don’t know whether that was your thought or not but I just wanted to be clear about it. It turns out that MMR is usually given around the time that autism commonly begins to show its earliest manifestations, so one might suspect an association on that basis, but that should only be taken as a need for research, not as any proof of causation. But we now know that the incidence of autism is identical in vaccinated vs. unvaccinated children, and there is enough data to assert that whatever is responsible for the rise in incidence of autism, it does not appear to be MMR. In fact once you start looking at data on the population level there is nothing to suggest an association, and I don’t think we would even be having this conversation except for Dr. Wakefield’s fraudulent publication on the topic.

1a. thimerosal is its own topic, but similarly there has been no link found with autism. In fact thimerosal was removed from most vaccines (and reduced to only trace amounts in a few) around 2000, but the incidence of autism is not dropping since that change. Actually thimerosal was used as far back as the 1930’s, long before the rise in autism we are now seeing.

2. We give hepatitis B vaccination beginning in the newborn nursery. The main source for a baby to get hepatitis B is from the mother, so rapid immunization at birth is essential. This strategy has been very effective. Routine vaccination started in 1991 and has resulted in greater than 80% reduction in hepatitis B incidence.

3. Yes, with the incidence of more available vaccines, we cluster more per visit. The schedule is specifically designed to produce an adequate immune response. It turns out that giving multiple vaccines together results in a better immune response than spacing them out which will result in overlapping of the time periods of generating the immune response. There are also practical issues of trying to implement immunizations in the most cost-effective way and also to get each applicable series completed as soon as possible for the best protection during the most vulnerable times in the child’s life, so combination vaccines at single visits are logical ways to achieve those objectives.

I hope that helps, but I realize we are only scratching the surface here, since there has been such a volume of so many things written on the topic, so I’ll try to answer any other questions you might have.

Thiomersol is not an issue in vaccines used in North America. It is used in minute amounts in multi-dose vials that cannot be guaranteed to maintain cold chain storage. For example, clinics run by relief agencies in unstable countries. It is not used as a preservative in single use vials that are stored in the fridge.

I’m a resident in family medicine and I think many of my patients would benefit from this information in the clear and sensitive way you present it. Do you mind if I share it with them and tweet about it? Obviously I’ll credit you.

Thank you for your article. I have read several articles that say there is a preponderance of evidence supporting statements similar to what you wrote but no one ever backs it up with citations. Can you cite several academic journal articles that would support your statements? I have always vaccinated my children but have been curious about reading academic articles for myself. Thank you.

I will collect some references for you. Was there a particular aspect of the article for which you were looking for the underlying evidence?

The largest study of MMR vaccine safety vis-a-vis worry about causation for autism was the Denmark study of over 500,000 children. The rate of autism did not differ between the 400,000 vaccinated children vs. the 100,000 unvaccinated children. See N Engl J Med, Vol. 347, No. 19, November 7, 2002 on the web at http://www.nejm.org/doi/pdf/10.1056/NEJMoa021134. Other more recent studies have continued to show no link between MMR and autism–see JAMA, 2015;313(15):1534-1540, web link to the abstract at http://jama.jamanetwork.com/article.aspx?articleid=2275444